Receiver on a cap system??

[Abe]

If you had a syatem which used capillary tubing as a metering device, and you "retain" the receiver ...........what will happen?

This "engineer" installed a 3/4 hp Le Unite compressor running a small coldroom, using a cap tube, and left the receiver connected

System goes in deep vacuum, then rises in pressure again. Keeps doing this. He says its moisture, and changed the drier

I said.........crap, you cant have a receiver connected in line. Take it out

And I did.........system is charming along now

Was I right???

[Prof Sporlan]

Was I right???

Yes...

A/C and refrigeration systems using cap tubes or short tube restrictors are critically charged systems. One must charge these systems with a relatively exact amount of refrigerant to get them working properly.

Systems employing receivers are, by definition, non-critically charged systems. These systems require an expansion device which can modulate the flow of refrigerant, e.g., a thermostatic expansion valve.

[farfield]

Has our peer above mentioned captube systems are critcle charged. If memory serves me correctly the captube (or a part of it acts as the reciever). Captubes have flash gas in it. At the inlet there is liquid and has rtefrigerant travels through captube refrigerant becomes saturated vapor by the time it exits the captube into the evaporator. HAs the load and ambient conditions change the length of the tube containing the liquid change slightly. This is what makes them so criticle to charge.

You did the correct thing. Ive seen the same thing. I guess this guy has been out everywhere, leaving in recievers.

[zolar1]

Would a drier act as a receiver of sorts?

[Prof Sporlan]

Would a drier act as a receiver of sorts?

It does, of sorts...

The additional refrigerant the filter-drier holds is available from the manufacturer for those who want to weigh in the exact charge.

It's unlikely you'll see system operating problems by applying a reasonably sized filter-drier to a cap tube system. Of course, all bets are off if you install a 4 core filter-drier shell to one of these systems...

[superheat]

Drier would not be a receiver because the level of ***** in the drier would not change much. At higher pressure, it might hold a little more *****. A reciever would have to be some kind of variable capacity device. Drier would effect the charge of the system though.

[Preston Roy Powell]

Yes take the reciever out. And dont you use very a large drier. If you are going to use the Condensing unit with a reciever change it to a TXV let the system go. We had a system(reachin refrigerator) that 2 tech. had gone out on the system always showed low charge. So i got the call on the weekend. I took the call went out and Found Captube evap which was be feed by a receiver system. the Fix.. Well!! I recovered the system. then valve off the receiver and compressor re-ran the liguid line added the TXV install new drier, and sight glass. Then evacuated the system, used a micro guage to ckeck for leaks. Also found the compressor was r-134a compatable. recharged with r-134a(weighed in, also using sight glass). Last heard from manager, "this box has never been this cold." also some one changed the condensing unit out because r-12 was getting to high...

[abcdefg1675]

My freezer has cap tubing and a receiver... Im assuming its used to pull a high vaccume on the evaporator for cold temps. am i right?

[Preston Roy Powell]

THis system is a built in refrigerator that is in a line. Originally it was R-12. The condensing unit didnot have a reciever. Some other company can in and changed the condensing unit which had now has a reciever on it. The system never worked properly. So I cut the cap tubes(2) off the evaporator. ANd Had a distribitor for the evaporator on hand ready to fix problem. Now it refrigerates properly and keeps the compressor at proper temp, plus not a noisy,.. THe Problem is fixed customer happy

[Gary]

My freezer has cap tubing and a receiver... Im assuming its used to pull a high vaccume on the evaporator for cold temps. am i right?

It is highly unlikely that your freezer has a receiver, and if it does then it shouldn't be there. Whatsmore, that is not the purpose of a receiver. The only thing pulling the pressure down on the evaporator is the compressor.